In my lazy saga of trying to track down my drivetrain slack... I came to the following thoughts:
-> There is some slack, but not a whole bunch. Just enough to be a pain if you don't know how to drive the truck with a gentle touch.
-> This slack hasn't changed over the last 100,000 km, except for when I installed new shocks (badly needed) - then it became slightly better
-> Fuel economy and performance is good (stock engine power)

...so, I thought... what could cause these types of symptoms? If it was a bearing that was bearing out and allowing extra play, you would expect it to worse over time. It is the same in each gear. We've lifted the axle and played with rotating the wheels back and forth - the play appears to be north of the driveshaft.

Could it be broken clutch disc springs? This would seem to allow about the right about of driveline slack, and explain why this problem hasn't become worse over time. Is there anyway short of removing the tranny to check/verify?

If this is the problem, what is a good clutch to replace it with? I'd rather not spend a bunch on money, but I'd also rather put my last clutch into the truck. I may add some modifications later - a #11 or #10 plate, change the timing a bit, etc... to bring it to "current new truck" power... but I don't want or need huge amounts of power, or problems that go with them. I was looking at the SBC 12.25 clutches - but they warn to avoid towing with them. I don't tow a whole lot, but don't want to have to worry about the clutch if I do tow and upgrade the power somewhat. A 13" upgrade kit is ~800 for the SBC O and 1000 for the OFE, which seems to be getting pretty rich for a clutch.

Also... how long does it take the average shade tree mechanic to remove and reinstall the clutch/tranny - and what do you guys use to remove the shift rod (only special tool I saw in the factory manual).

Thanks!

 

If you had broken clutch springs you'd have quite noticable slippage in the clutch. Sounds like a gear or bearing problem in the tranny, if the play is out of spec. Do you have an specs on how much play there should be? You don't mention any, so that's why I ask.
Is there a PTO cover on the side of the tranny? If so, pulling that should give you a good view inside to look and possibly feel around for problems. You'd also be able to run a magent around the bottom and see if any bearing parts come back.

Chris

 

I mean the damper springs on the disc itself - not the pressure plate. From what I understand, the disc is essentially two pieces normally held in relatively constant position to each other via some strong springs, but if these are missing, the disc can rotate until the hub/disc collides with rivits on the other/something else.

The transfer case has been removed before, and the tail of the transmission pulled to put 5th gear back together. The shop that did that hadn't reported anything else awry, although perhaps it would be impossible to tell.

I can't think of anything else that would cause this kind of symptom... the transmission shifts well (minus slack being annoying), power and economy is good, the only unusual noise is an occasional clunk if you try to shift quickly (could be clutch again?)... I would imagine that if it was a blown bearing, the whole tranny would have blown up sometime in the last 100,000 k... or if it was a gear lash issue, it would have become even marginally worse in this time.

 

http://65corvette.nonethewiser.net/t..._diagnosis.pdf

See # 5 and 6 on pages 6 and 7 for what I'm trying to describe.